Pushing an LPR as a MPR upper stage

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I'm planning to do something similar this weekend. I made a booster for my BT60 Estes Magnum clone. It's maiden flight will be F23-4-->C11-7, with an Eggtimer Quantum lighting the sustainer and motor eject for the booster's recovery deployment. I'm trying to keep everything under 2k ft so I can see the whole flight profile. I'm just hoping for cooperative weather on Saturday.

Good luck with your flight.

How did it go????
 
Ordered the 45C 300mah Turnigy Lipo that Cris recommends, is all. And spent some time making fins to replace the ones missing on my 1/100 Saturn 1B kit. And asked Jackie to hold motors for my for ECOF. And poured cider for the 6000 attendees at The Great Taste of the Midwest.

Looking forward to hearing how this works, hope it does well. What kind of cider/apples?
 
Our partner orchard grows about 200 varieties of apples and pears, including about 60 that are English and French high tannin true cider apples and perry pears just for us.

We currently make:
3 sparkling champagne method
7 draft style (4 traditional, 3 flavored)
4 still/table (2 0-residual sugar still ciders, 2 medium sweet wine-like
4 fortified dessert
5 brandies (2 plum, pear, apple, grape)
And our sorghum whiskey at two strengths.
 
I'll take one of each. Sounds wonderful.

i concur. I actually made Mulberry wine one year. Turns out it takes about 40 man hours per liter. and another to get the purple stains out of everything. I'll definitely be stopping in.
 
I just realized my mental calendar was a week off. No club flying for me until the end of September. Maybe until next Jan/Feb.
 
I made my first attempt at F79-D9 at the last Tripoli WI launch. Beautiful day. No second stage ignition, and also no separation, so the stack was recovered without damage.

On the pad with my elder son.
IMG_0107.jpg

Flight line video
https://youtu.be/Sbc2BstlnRc

The lack of staging turned out to be a PICNIC problem. I hadn’t updated my sim with the real masses, and it turns out I had the airstart altitude check set too high. Velocity check -might- have been okay. For that matter, the F79 booster stays so low that the Quantum minimum airstart altitude is an issue. But I have this G88 handy here...

Sim is now updated, and now matches the data from both prior flights pretty well. There’s a half second mismatch that lingers, I suspect my avbay isn’t vented well enough.

I’ve also fixed a few outstanding issues:
I’ve CA’d down the spot where the fin papering lifted.
I’ve received my 300mAh, 45C, Cris-recommended Lopo, and tested it against several igniter types with great success.
I’ve addressed needing more pyro events on a full-up I-G flight by putting a Quark in the PNC60NA Apache nosecone. Mini HED!
And I’ve added vent holes for the avbay.

Time to try again.
 
I made my first attempt at F79-D9 at the last Tripoli WI launch. Beautiful day. No second stage ignition, and also no separation, so the stack was recovered without damage.

On the pad with my elder son.
View attachment 341391

Flight line video
https://youtu.be/Sbc2BstlnRc

The lack of staging turned out to be a PICNIC problem. I hadn’t updated my sim with the real masses, and it turns out I had the airstart altitude check set too high. Velocity check -might- have been okay. For that matter, the F79 booster stays so low that the Quantum minimum airstart altitude is an issue. But I have this G88 handy here...

Sim is now updated, and now matches the data from both prior flights pretty well. There’s a half second mismatch that lingers, I suspect my avbay isn’t vented well enough.

I’ve also fixed a few outstanding issues:
I’ve CA’d down the spot where the fin papering lifted.
I’ve received my 300mAh, 45C, Cris-recommended Lopo, and tested it against several igniter types with great success.
I’ve addressed needing more pyro events on a full-up I-G flight by putting a Quark in the PNC60NA Apache nosecone. Mini HED!
And I’ve added vent holes for the avbay.

Time to try again.

That is similar to the issue I had with my first attempt at electronic staging. The Quantum is designed for HPR, so if you don't have powerful motors, you won't meet the minimum thresholds for staging. An accurate sim is a must.

It sounds like you are working out the bugs. I still haven't pulled it off successfully either, but I think it should work next time. I just need the weather to start cooperating.
 
Oh, I don’t know about the Quantum being an HPR critter. We know that Cris did the flight testing on Estes Mongoose D-D flights. If anything, I think the code reflects Cris’ preference for a high G liftoff. The F79 averaged 6G, peak was probably about 9. Cris -really- recommends >10.

I’m also feeling ‘this time fer sure’.


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Oh, I don’t know about the Quantum being an HPR critter. We know that Cris did the flight testing on Estes Mongoose D-D flights. If anything, I think the code reflects Cris’ preference for a high G liftoff. The F79 averaged 6G, peak was probably about 9. Cris -really- recommends >10.

I’m also feeling ‘this time fer sure’.


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According to Cris's manual though he does not recommend the use of Vmax/W9 motors.
 
Not many electronics like W9 anyways.

Since when, most of our electronics work just fine with Warp9 and Vmax propellant. Please read the Eggtimer Quantum manual for Cris's exact reason why he does not recommend them for use as booster motors.
 
Second try at staging: drag separated at the payload bay. Hasn’t done -that- before.

[video=youtube;fcc1Z1k2SIQ]https://www.youtube.com/watch?v=fcc1Z1k2SIQ[/video]


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Looking rely good! Could we see some close ups of how you ran the wiring for the sustainer, I am about to start a mpr to lpr 2 stager myself and am trying to gather as much details on other people's methods as possible.

Also do you use your quantum for sustainer ignition and apogee deployment, or do you use motor ejection?


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I don’t have a picture of the sustainer body internal handy - I ran two 1/8” OD (about) poly lines down the inside of the sustainer, through holes carved in the centering rings. Just above the motor mount they are wrapped with foil tape, but aren’t currently taped to the inside of the tube.

I do have pics of the Eggfinder and Quantum.

IMG_0126.jpg
IMG_0127.jpg
IMG_0128.jpg
IMG_0129.jpg

The Quantum handles the airstart and a charge at noseover to back up the motor eject - or instead of motor eject in the case of long required coast time.

A Quark in the nosecone handles main ejection.

Flown as a boosted dart, the Quantum can handle both drogue and main. In airstart mode, it can still do the drogue. I’m using either drag or blast separation here.
 
IMG_0151.jpg

Third flight.
Igniter fired - didn’t light the AT D9
Backup drogue fired - didn’t separate the payload bay after I increased its friction fit to prevent drag separation.
Main chute charge didn’t fire - might have tried by the looks of the ematch. Surface is roughened compared to new. Maybe the 1S Lipo didn’t like the 30F temp?
 
View attachment 342308

Third flight.
Igniter fired - didn’t light the AT D9
Backup drogue fired - didn’t separate the payload bay after I increased its friction fit to prevent drag separation.
Main chute charge didn’t fire - might have tried by the looks of the ematch. Surface is roughened compared to new. Maybe the 1S Lipo didn’t like the 30F temp?

Bummer Charles, looks partly salvageable though. I could almost bet the problem was the 1S Lipo, iirc Cris recommends 2S LiPos for EggProducts. I missed the opportunity to fly my two stage Nike-Cajun today due to the launch being cancelled for rain and 20-30mph winds.
 
All the electronics made it.
The OOP Estes 5560 transition made it.
The fin can is fine.

So I’ll rebuild and keep trying.


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That sucks!!! I have been wondering if my my 2-stage project was cursed too. But I’ve got at least one more attempt in me. Keep up the good work!
 
OK, so a couple of tubing couplers later, it's all fixed up again - if slightly less pretty than before.

I got in a -successful- ground test last night, both main and drogue.

The first attempt used the cap off one of those little between-tooth brushes. Ematch threaded through a hole in the bottom, 0.5g BP filled in around the match head, dog barf -packed- on top of the BP, and closed up with electrical tape. It was face (tape) down, in the gap between the motor and the centering rings, when it simply blew a hole through the tubing. With a loud bang.

I also reduced the amount of tape on the payload bay shoulder. Still 1 layer, but only about an inch of circumference - not most of the way around.

So I changed tack and tried again. This time, I used a 2mL centrifuge vial. The ones I have handy have threaded caps. I put the 0.5g BP in, put the ematch face down on top of it, added a little dogbarf - unpacked-, and slid the cap (drilled AND scored) over the lead and threaded it on. So now the ematch wire keeps the charge facing up, not directed towards the body tube. In free air, it still goes off with a bang. In the tube, it made a bit of a woof and popped everything out.

Ready to try again next launch. I'm going to switch over to a CTI Apache motor, though. I feel the need for a little more reliable lighting.
 
Ok, success! At least mixed success.

I got in a flight this Sunday, after a trying morning re-tuning the seamer on my canning line. Some kind of fault knocked the dies out of alignment, and I’ve only done that task once before, so it took over an hour to figure out the problem and bring it back into spec. Luckily, my distiller (and wife) let me stick to plan and fly, even if it was at the end of the day and the club was packing up the away pad at the same time.

Try 4 was a CTI G131SS to CTI F51BS. I decided to go to 3G in the booster to get further away from the minimum safety limits. I ditched the hard to light AT D9 in favor of pellet assisted CTI. The original plan was E22SS, but Wildman was out of 1G casings.

[video=youtube;oBMEKb-iHzM]https://www.youtube.com/watch?v=oBMEKb-iHzM[/video]

Booster recover was nominal, using my home brew Quark based chute release.

Apogee was just shy of 2800’. I lost sight of the Apache (BT55 based) on the way down (drogueless). The on-board Eggfinder led me straight to it. The Apache Quark appears to have fired the main at 300’, but an undersized charge failed to pop it clear. (It worked in ground testing. )

The Apache sustained pretty heavy damage to the base and 1 fin. Blown out and delaminated. I’m currently thinking possible blow out from the blast separation followed by >700fps speed.

IMG_1525099105.006681.jpg

I think the way I have tubing for the ignition wires running through the fin can centering rings means I duct base air pressure up to the altimeter. And I forgot to add vents after the last rebuild. So I saw a really big pressure swing, first positive from the separation event, then negative, I’m thinking from plume Venturi-like affects during the sustainer burn.

IMG_1525099310.107340.jpg

So now I have to decide if I’m going to retire the Apache, or rebuild the fin can. Again.
 
Congrats!!!!

That counts as a win in my book. I like the idea of pushing the booster portion of the flight harder. I think that is the biggest change that I have to wrap my mind around when graduating from LPR to HPR staging.
 
If you rebuild use a piece of poster tack ( non permanent putty adhesive) over where the wires go into the fincan on the motor side that may prevent the pressure spike in the future.

Oh, and congrats!
 
If you rebuild use a piece of poster tack ( non permanent putty adhesive) over where the wires go into the fincan on the motor side that may prevent the pressure spike in the future.

Oh, and congrats!

Thanks for the tip. I think I glued the tubing in place, but I was thinking of something similar around the wires to plug up the ends.
 
Congrats!!!!

That counts as a win in my book. I like the idea of pushing the booster portion of the flight harder. I think that is the biggest change that I have to wrap my mind around when graduating from LPR to HPR staging.

Everything stages so much higher than BP direct staging - even 29mm F-F. If I rebuild, I’ll drop back to the G88 to E22. I’ve gotten it to work. It’s really stable, so I’m more comfortable relaxing the min altitude constraint and using just the min V.

And now I’ve seen how this size rocket disappears at 2800’, let alone the 7000’ that a full up impulse flight would be.
 
I suspect (after reading the max speed) that the damage may have been caused by flutter. once the tube started to fail, the fin was able to flex far enough to de-skin itself.
Rex
 
Hmmm... I seem to recall that I cracked a fin joint on an earlier flight. I wonder if it was the one that failed - that my repair was insufficient. I’ll have to look more closely b
 
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